An investigation to detect food-stimulated gastro-oesophageal (GE) reflux was carried out in 54 consecutive fasting patients, 35 of whom experienced reflux while 19 did not. All patients then received a standard meal (566 kcal), and the investigation was repeated 1 h later. Out of the 35 with GE reflux in the fasting state, 33 also had GE reflux in the postprandial state, and 17 of the 19 patients with no GE reflux while fasting also had none in the postprandial state. It is concluded that the radiological method can identify most patients in whom food-stimulated GE reflux could be of clinical significance.